Normalization of Ring Currents

FIGURE 12.7 In view that perylene has non-interacting naphthalene subunits, it can, on this model, be viewed as two naphthalene molecules. 

FIGURE 12.8 Nine Kekule valence structures of perylene, in all of which the central bonds connecting naphthalene subunits are devoid of conjugation. 

As we can see, naphthalene subunits in perylene, instead of having bond currents the same as in naphthalene, have significantly lower bond currents. It is not important how small or how great the difference is in this model, there should be no difference in bond currents between benzene rings of naphthalene and perylene, clearly pointing to an inherent inconsistency of the model. 

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